 /*
  * $Header: /cvshome/build/org.osgi.framework/src/org/osgi/framework/ServiceListener.java,v 1.15 2007/02/20 00:16:30 hargrave Exp $
  *
  * Copyright (c) OSGi Alliance (2000, 2007). All Rights Reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  * http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package org.osgi.framework;

 import java.util.EventListener ;

 /**
  * A <code>ServiceEvent</code> listener. <code>ServiceListener</code> is a
  * listener interface that may be implemented by a bundle developer. When a
  * <code>ServiceEvent</code> is fired, it is synchronously delivered to a
  * <code>ServiceListener</code>. The Framework may deliver
  * <code>ServiceEvent</code> objects to a <code>ServiceListener</code> out
  * of order and may concurrently call and/or reenter a
  * <code>ServiceListener</code>.
  *
  * <p>
  * A <code>ServiceListener</code> object is registered with the Framework
  * using the <code>BundleContext.addServiceListener</code> method.
  * <code>ServiceListener</code> objects are called with a
  * <code>ServiceEvent</code> object when a service is registered, modified, or
  * is in the process of unregistering.
  *
  * <p>
  * <code>ServiceEvent</code> object delivery to <code>ServiceListener</code>
  * objects is filtered by the filter specified when the listener was registered.
  * If the Java Runtime Environment supports permissions, then additional
  * filtering is done. <code>ServiceEvent</code> objects are only delivered to
  * the listener if the bundle which defines the listener object's class has the
  * appropriate <code>ServicePermission</code> to get the service using at
  * least one of the named classes under which the service was registered.
  *
  * <p>
  * <code>ServiceEvent</code> object delivery to <code>ServiceListener</code>
  * objects is further filtered according to package sources as defined in
  * {@link ServiceReference#isAssignableTo(Bundle, String)}.
  *
  * @see ServiceEvent
  * @see ServicePermission
  * @ThreadSafe
  * @version $Revision: 1.15 $
  */

 public interface ServiceListener extends EventListener {
     /**
      * Receives notification that a service has had a lifecycle change.
      *
      * @param event The <code>ServiceEvent</code> object.
      */
     public void serviceChanged(ServiceEvent event);
 }

